I think you should learn the basic phrases in each of the languages - carry phrasebooks or dictionaries, anything that might be helpful in understanding the other languages. In the common and mainstream travel sites there will likely be English signs and translations, but if you travel out of those zones, you're pretty much screwed. It sucks when you can't really speak to anyone and are just left to enjoy the scenery - the travel experience is always much better when you get to talk to the locals. And try not to travel by train at night. Trains are a common form of transportation in Eastern Europe. However, in Poland, I wouldn't recommend boarding one for the overnight ride. You might be robbed while asleep.